Printers can print specific information or content onto many different types of print media (e.g., labels having a releasable liner). In order to detect different types of print media and/or liner materials, printers (e.g., thermal-transfer printers) may include a sensor arrangement (e.g., optical sensors).
A typical printer sensor system, such as an optical sensor system, is mounted in a perpendicular arrangement with respect to the surface of the print media. The optical sensor detects print media type by measuring detected light values that are dependent upon the transparency and/or reflectivity of the media and/or its liner (transmissive, reflective, etc.). The difference between the transparency reading of the combination of the print media and liner when compared to the liner alone enables the printer to, for example, detect the edges of the print media. If the type of print medium is not accurately detected, the medium may be misaligned and the content improperly printed (i.e., the content may be printed onto the liner rather than the label).
As described above, however, the typical printer optical sensor system requires that there be a detectable difference between the two detected light values (i.e., a different value for the print media and liner versus the liner alone) to detect the edges of the print media. As a result, typical printers are unable to accurately detect transparent media on transparent liner without the addition of pre-printed marks, or some other type of identification, in order to facilitate correct detection and classification of the print media and/or print liner. Otherwise, a user may need to manually mark the transparent media or make other manual changes to the printer configuration in order to correctly/accurately print onto the transparent media.
Therefore, a need exists for more effective printer systems, including but not limited to printer sensor systems that facilitate accurate detection of transparent print media and/or print liner.